const fib = require( './index' );

test( 'Fib function is defined', () => {
  expect( typeof fib ).toEqual( 'function' );
} );

test( 'calculates correct fib value for 1', () => {
  expect( fib( 1 ) ).toEqual( 1 );
} );

test( 'calculates correct fib value for 2', () => {
  expect( fib( 2 ) ).toEqual( 1 );
} );

test( 'calculates correct fib value for 3', () => {
  expect( fib( 3 ) ).toEqual( 2 );
} );

test( 'calculates correct fib value for 4', () => {
  expect( fib( 4 ) ).toEqual( 3 );
} );

test( 'calculates correct fib value for 15', () => {
  expect( fib( 39 ) ).toEqual( 63245986 );
} );
